Thailand. (Burma Overland Mail). 1901. India postal stationery envelope 'half anna' green upgraded with India SG 89, 1a plum (pair) tied by Sandaway date stamp '4th Ap 01' addressed 'To Superintendent of Survey, Bankaka, Bancac (Siam) via Rangoon' with Singapore transit 'April 18' and vernacular Bangkok arrival '24/4' and Bangkok/ 5 receiver with seven different arrival cachets on reverse.